when<TResult extends Object?> method
- @optionalTypeArgs
A switch
-like method, using callbacks.
As opposed to map
, this offers destructuring.
It is equivalent to doing:
switch (sealedClass) {
case Subclass(:final field):
return ...;
case Subclass2(:final field2):
return ...;
}
Implementation
@optionalTypeArgs TResult when<TResult extends Object?>({required TResult Function( Map<String, String>? headers) formData,required TResult Function( Map<String, String>? headers) basic,required TResult Function( Map<String, String>? headers) data,}) {final _that = this;
switch (_that) {
case _FormData():
return formData(_that.headers);case _Basic():
return basic(_that.headers);case _Data():
return data(_that.headers);}
}